LONDON, England (CNN) -- As furor grows over the mistreatment of Iraqi detainees, a report from a human rights group has charged that British troops occupying southern Iraq killed a dozen civilians who posed no threat to them.

Many of those killings have not been investigated by the British military, and the families of the victims have not been compensated, according to a report released on Tuesday in London by Amnesty International.

"In several cases documented by Amnesty International, UK soldiers opened fire and killed Iraqi civilians in circumstances where there was apparently no imminent threat of death or serious injury to themselves or others," the report says.

The Ministry of Defence said it was aware of the Amnesty report but had not been able to examine its allegations in detail. A spokeswoman told CNN: "We are aware of the concerns expressed by Amnesty and are considering the points raised. We will respond in detail in due course.

"Some of the allegations if true may give grounds for criminal prosecution. Some cases are indeed already the subject of legal action and for this reason we are unable to comment further."

The ministry spokeswoman added: "We take our obligations under international law seriously and attach great importance to upholding human rights in all circumstances."

The Amnesty report listed examples of 12 civilians who were apparently killed by British forces under questionable circumstances, including the shooting of an eight-year-old girl who was standing with a group of children when a British patrol moved into her town.

A report on the August 21 shooting incident from the First Battalion of the King's Regiment said mobs threw stones at the troops as they drove into Karmat Ali, and one soldier fired a warning shot to disperse the crowds.

However, Hanan Salih Matrood's family said there was no stone-throwing when the British soldiers moved in.

An eyewitness told Amnesty investigators that a few British soldiers got out of an armored vehicle at the entrance to the alley where Hanan lived.

The witness said a group of children, including Hanan, were attracted by the soldiers and stood more than 70 meters (200 feet) away, observing them.

"Suddenly a soldier aimed and fired a shot which hit Hanan in her lower torso," the report says.

The British soldiers took the young girl to a hospital, but she died the next day.

Hanan's family said British military police took pictures of the scene and interviewed witnesses the day after the shooting.

But no investigation was launched into the killing by British military authorities, according to information from the UK Minister of State for the Armed Forces, the Amnesty report says.

Britain's Ministry of Defense has said that UK forces have been involved in the killing of 37 civilians since May 1, 2003, according to the report.

Amnesty also criticized the British military's investigative procedures, saying officers had too much discretion in deciding whether to launch an inquiry when a civilian was killed. The group also said investigations should be far more open.

"The investigations have been shrouded in secrecy -- some victims have not even been aware that they have been opened," the report said. "Families of victims have also not been given adequate information on how to apply for compensation."

The report also criticized the process by which Iraqi families could claim compensation for their relatives' deaths, saying it was too difficult and the site where the necessary papers could be obtained was far away and largely inaccessible, especially for poorer families who could not afford to travel.

'Wrong information'

"Families are frequently given no information on how to lodge a compensation claim for the killing of their relatives," the report says.

"In some cases, they are given the wrong information, including that responsibility for compensation would rest with a new Iraqi government."

The report also describes political and "moral" killings by armed groups in the British-administered south.

It says dozens of former Ba'ath party members, shopkeepers who sell alcohol and those who sell videos and music have been killed, often in broad daylight, and no prosecutions have been brought.

It says British forces and Iraqi police have failed the people in the south by not preventing such killings or prosecuting and punishing those responsible for them.

Amnesty International called on British authorities to establish a civilian-led mechanism to investigate all suspected killings of Iraqi civilians by British forces and ensure that those forces can communicate with Iraqis by making competent interpreters available.

The group said the report was based on information gathered by its delegates in February and March.